*4.11. FTIR Spectra Analysis*

The study employed an Infrared Tensor 37 instrument (InfraRed Bruker, Ettlingen, Germany) to evaluate the chemical interaction among the constituents of the film matrix. The Fourier Transform Infrared Spectroscopy (FTIR) instrument was configured to conduct 32 scans across a wide spectral region spanning from 400 to 4000 cm−<sup>1</sup> .
